Gears - Motion Passed Along
When two gears mesh, turning one makes the other turn in the opposite direction.
A small gear driving a larger gear makes the larger one turn more slowly but with greater torque. A large gear driving a smaller one makes the smaller gear turn faster.
The speed ratio depends on the number of teeth on the gears.
This is a sculpture, but you can turn one of the smaller gears and watch how the motion travels to the other.
Additional Information
Two meshed gears always spin in opposite directions; add a third gear and the first and last spin the same way again.
The gear ratio — the difference in tooth count between two gears — determines exactly how much speed or force gets traded off.
Bicycles, clocks, and car transmissions all use gear ratios to match an engine’s or rider’s power to what’s actually needed at the wheels.
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